Hemispheric Lateralisation and split brain research Flashcards
What is hemispheric lateralisation?
the idea that the two hemispheres of the brain are functionally different/ with certain mental processes being mainly controlled by one hemisphere rather than the other (e.g. language lateralised to the left hemisphere).
What’s are the two hemispheres connected by?
the corpus callosum
What is the corpus callosum?
a bundle of nerve fibres that allows the two areas to communicate
Where is spatial awareness lateralised?
to the right
What does spilt-brain research typically involve?
involves severe epileptic patients who have had their hemispheres surgically separated by cutting their corpus callosum, which is in order to reduce the severity of their epileptic seizures-allows researchers to investigate the extent to which brain functions are lateralised.
What was sperry’s procedure?
-participant sits close to a screen + fixates on a dot. A diffetent word is simultaneously presented to the left and right of the dot for 1/10/second so there is no time for the participant to move their eyes to view both words. There is a selection of objects relating to the words behind the screen.
Participants are then asked to:
• Say the words they see on the screen.
• Pick up objects with their left hand which represents what they see.
What were the findings of sperry’s research?
When the word ‘key’ was presented to the left visualtield simultaneously with the word ring’ to the right visual field, participants:
•said ring
• Picked up the key with her let hand.
What was the conclusion for sperry’s?
Both hemispheres are responding independently and are not able to integrate the information because of the severed corpus callosum.
Why do participants say ring in sperry’s research (conclusion)?
-image of the word in their right visual field passes to the visual cortex of the left hemisphere of the brain (contains language centres so the person is able to vocally produce the word ‘ring’.)
Why do participants only pick up key in sperry’s research?
-image of the word in their left visual field passes to the visual cortex of the right hemisphere of the brain (contains spatial processing abilities and the right motor cortex, which controls muscles on the left side of the body, which enables the left hand to pick up the object relating to word ‘key’)
Overall, what does split brain research suggest?
there is hemispheric lateralisation in the brain: language is lateralised to the left hemisphere and visual-spatial processing is lateralised to the right hemisphere.
